Milly is a distinctive girls' name in United States, ranking #1949 in 2017 with 103 recorded births. The name reached its all-time peak in 2014 with 129 births ranking #1657. Since 1996, the popularity has increased by 836.4%. In 2017, approximately 1 in every 16,756 girls born was named Milly. STABLE Recent data shows the name is currently stable.